What is the most common type of virus?

In computer system security, a virus is a type of destructive code or program that self-replicates by placing its code into other programs. As a result, contaminated computer systems can spread out the virus to other computer systems. Viruses are typically spread by e-mail accessories, social networks links, and online advertisements. The most typical kind of computer system virus is theTrojan horse, which techniques users into clicking a harmful link or email attachment. i was reading this